1 files changed, 109 insertions, 0 deletions
diff --git a/drivers/clk/clk_vexpress_osc.c b/drivers/clk/clk_vexpress_osc.c
new file mode 100644
index 0000000000..7fef4b2e31
--- /dev/null
+++ b/drivers/clk/clk_vexpress_osc.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 Arm Ltd
+ * Author: Liviu Dudau <liviu.dudau@foss.arm.com>
+ *
+ */
+#define DEBUG
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm.h>
+#include <dm/lists.h>
+#include <errno.h>
+#include <misc.h>
+
+#define CLK_FUNCTION		BIT(20)
+
+struct vexpress_osc_clk_priv {
+	u8 osc;
+	ulong rate_min;
+	ulong rate_max;
+};
+
+static ulong vexpress_osc_clk_get_rate(struct clk *clk)
+{
+	int err;
+	u32 data;
+	struct udevice *vexpress_cfg = dev_get_parent(clk->dev);
+	struct vexpress_osc_clk_priv *priv = dev_get_priv(clk->dev);
+
+	data = CLK_FUNCTION | priv->osc;
+	err = misc_read(vexpress_cfg, 0, &data, sizeof(data));
+	if (err)
+		return err;
+
+	return data;
+}
+
+#ifndef CONFIG_SPL_BUILD
+static ulong vexpress_osc_clk_set_rate(struct clk *clk, ulong rate)
+{
+	int err;
+	u32 buffer[2];
+	struct udevice *vexpress_cfg = dev_get_parent(clk->dev);
+	struct vexpress_osc_clk_priv *priv = dev_get_priv(clk->dev);
+
+	if (rate < priv->rate_min || rate > priv->rate_max)
+		return -EINVAL;
+
+	/*
+	 * we are sending the parent the info about the oscillator
+	 * and the value we want to set
+	 */
+	buffer[0] = CLK_FUNCTION | priv->osc;
+	buffer[1] = rate;
+	err = misc_write(vexpress_cfg, 0, buffer, 2 * sizeof(u32));
+	if (err)
+		return err;
+
+	return rate;
+}
+#endif
+
+static struct clk_ops vexpress_osc_clk_ops = {
+	.get_rate = vexpress_osc_clk_get_rate,
+#ifndef CONFIG_SPL_BUILD
+	.set_rate = vexpress_osc_clk_set_rate,
+#endif
+};
+
+static int vexpress_osc_clk_probe(struct udevice *dev)
+{
+	struct vexpress_osc_clk_priv *priv = dev_get_priv(dev);
+	u32 values[2];
+	int err;
+
+	err = dev_read_u32_array(dev, "freq-range", values, 2);
+	if (err)
+		return err;
+	priv->rate_min = values[0];
+	priv->rate_max = values[1];
+
+	err = dev_read_u32_array(dev, "arm,vexpress-sysreg,func", values, 2);
+	if (err)
+		return err;
+
+	if (values[0] != 1) {
+		dev_err(dev, "Invalid VExpress function for clock, must be '1'");
+		return -EINVAL;
+	}
+	priv->osc = values[1];
+	debug("clk \"%s%d\", min freq %luHz, max freq %luHz\n", dev->name,
+	      priv->osc, priv->rate_min, priv->rate_max);
+
+	return 0;
+}
+
+static const struct udevice_id vexpress_osc_clk_ids[] = {
+	{ .compatible = "arm,vexpress-osc", },
+	{}
+};
+
+U_BOOT_DRIVER(vexpress_osc_clk) = {
+	.name = "vexpress_osc_clk",
+	.id = UCLASS_CLK,
+	.of_match = vexpress_osc_clk_ids,
+	.ops = &vexpress_osc_clk_ops,
+	.priv_auto_alloc_size = sizeof(struct vexpress_osc_clk_priv),
+	.probe = vexpress_osc_clk_probe,
+};